Automotive signal light control switch



Oct. 27, 1953 A. HOPKIN, JR

AUTOMOTIVE SIGNAL LIGHT CONTROL SWITCH 5 Sheets-Sheet 1 Filed May 24. 1950 INVENTOR. ALFRED HOPK/N JR.

ATTORNEY Oct. 27, 1953 A. HOPKIN, JR

2,657,293 AUTOMOTIVE SIGNAL'LIGHT CONTROL SWITCH Filed Mayv24. 1950 32 INVENTOR.

ALFRED. HOPK/N JR BY mug)! ATTORNEYS.

Oct. 27, 1953 A. HOPKIN, JR 2,657,293

AUTOMOTIVE SIGNAL LIGHT CONTROL; SWITCH Filed May 24. 1950 5 Sheets-Sheet 3 INVENTOR. ALFRED HOPK/N JR ATTORNEYS.

Oct. 27, 1953 A. HOPKIN, JR 2,657,293

AUTOMOTIVE SIGNAL LIGHT CONTROL SWITCH Filed May 24. 1950 5 Sheets-Sheet 4 INVENTOR. ALFRED HOPK/N JR.

ATTORNEYS.

Oct. 27, 1953 A. HOPKIN, JR 2,657,293

AUTOMOTIVE SIGNAL LIGHT CONTROL SWITCH Filed May 24. 1950 5 Sheets-Sheet 5 FIG.

INVENTOR. ALFRED HOPK/N -\J"/1"- ATTORNEYS.

Patented Oct. 27, 1953 AUTOMOTIVE SIGNAL LIGHT CONTROL SWITCH Alfred Hopkin, Jr., Philadelphia, Pa., assignor to Arrow Safety Device Company, Mount Holly, N. J., a corporation of New Jersey Application May 24, 1950, Serial No. 163,988

14 Claims.

This invention relates to a control switch assembly and signal system employed for controlling turn and stop light signals such as are commonly used on motor vehicles. The switch assembly may be mounted on the steering column and operated by the driver or" the motor vehicle. The switch assembly provides a control for the signal'lights and also provides an indication to the driver of improper operation of the signal system.

This invention relates to an improvement of the signal switch assembly disclosed in the co-pending Thomas F. Young application Serial No. 81,665 filed March 16, 1949.

It is an object of this invention to provide a :control switch of simple, economical and practical construction which may be mounted on the steering column of a motor vehicle and manually operated by the driver to control turn signal lights :and which provides a pilot light which will indicate to the driver the existence of a failure in the turn and stop light signal system.

It is a further object of this invention to provide a control switch assembly which will automatically return to a neutral position after the expiration of a predetermined period of time after the operation thereof.

It is another object of this invention to provide a control switch assembly which will automatically return to a neutral position after the expiration of a predetermined period of time after the o eration thereof and in which the predetermined period may be extended when desired.

It is another object of this invention to provide a control switch assembly which after being manually moved to an operating position will be latched in that position and automatically released from that position after a predetermined period of time by the operation of a thermal eleinent.

It is another object of this invention to provide a control switch assembly which after being manually positioned in one of its operating positions will be latched in that position and will be released from that position after a predetermined period of time by the operation. of a thermal element, and which may immediately thereafter be latched into the other or" its operating positions when manually moved into that position and which after the expiration of a predetermined period of time will be released therefrom by the operation of a second thermal element.

These and other objects of the invention will become apparent from the following description when read in conjunction with'the accompanylng drawings, in which;

Figure 1 is an elevation of the switch assembly mounted on a steering column showing the case, the switch means and the mounting means in section;

Figure 2 is a plan view of the switch assembly taken with the switch case partly cut-away showing the section taken on the plane indicated by the trace 2- 2 in Figure 1;

Figure 3 is a plan'view of the switch assembly shown in Figure 1 with the switch case removed;

Figure 4 is an enlarged showing of a portion or the switch mechanism shown in Figure 3 with the switch in a neutral position;

Figure 5 is an enlarged showing of the same portion of the switch mechanism as shown in Figure 4 with the switch latched in an operative position;

Figure 6 is an enlarged showing of an alternate form of the portion of the invention shown in Figure 4 showing the switch in a neutral position;

Figure 7 is an enlarged showing of the portion of the alternate form of the invention shown in Figure 6 with the switch latched in an operative position;

Figure 8 is a section taken on the plane 8B' in Figure 7;

Figure 9 is an enlarged showing of another alternate form of the portion of the invention shown in Figure 4 showing the switch in a neutral position;

Figure 10 is an enlarged showing of the portion of the alternate form of the invention shown in Figure 9 with the switch latched inan operative position;

Figure 11 is a partially cut-away side elevation of the portion of the alternate form of the invention shown in Figure 9;

Figure 12 is a plan view of a portion of the switch assembly showing still another form of the invention; and

Figure 13 is a diagrammatic showing of the electrical circuit employed in all forms of the invention.

Referring to Figures 1-5 there is shown a stamped metal switch case 4 which is attached by the use of four screws 6, to a stamped metal switch case bottom member 8. Afiixed to the bottom member 8 are the bracket members I'D supporting the switch assembly base plate [2. The base plate i2 is made of a resin impregnated fibre-or other suitable insulating material and provides a mounting plate for the switch parts as will be hereinafter described.

The switch case is mounted on the steering column M by means of the steel strap I6 which is passed around the steering column, through slots is in the channel member and is folded back so that the ends the strap lay over the strap it against the steering column. The member 22 is a box-like member having an open end 2 2 adjacent to the steering column M. The edges 26 of the open end of the box are brought to bear firmly against the strap i6 and the folded back ends by the the head of screw 28. The screw 28 passes freely through the member 22 and the head of the screw rests upon member 22. The screw is threaded into the member 29. Thus, turning the screw draws the member 253 back into the box member 22 away from the steering column, pulling the strap tightly around the steering column, clamping the strap l6 and the ends thereof ll firmly between the edges 25 of the box member 22 and the steering column thereby rigidly mounting the box member 22 against the steering column. The hole 29 in the side of member 222 is provided as a sight hole to facilitate the insertion of the screw 28 through the threaded bore in the member it. After the member 7 22 is mounted to the steering column the switch case is attached thereto by screws 30.

Riveted to the base plate 52 are the brass contact strips M, 66, ill and 5d, the contact members 5i and 52, and the bracket 32. The bracket 32 is affixed to the base plate by rivets E l and contains a centrally located bore 38 in alignment the in switch assembly plate 52. Rotatably mounted in the bores 33 and 40, as hereinafter described, is the switch shaft The uppermost portion of the shaft 12 is of reduced diameter providing a mounting for the 68 looking it in position, preventing it from be ing withdrawn from the bores 10 and '12. It will he cvide at the ind moved inwardly or outwardly of the switch ease within the limits provided between the shaft 4.! and the turned down portion 82 of the bracket 55. Thus the end portion. iii! of the operating lever 68, which is provided to be gripped by the operator, may be positioned to his convenience.

The turned down portion 85 of the bracket 64 is elongated and curved and forms a close off plate back of the elongated slot in the switch case 4. The insulating member 54 is made of a resin impregnated fibre or other suitable insulating material and contains a central bore which is pressed over the reduced diameter serrated portion of the switch shaft if! and bears against the shaft shoulder formed thereby. The insulating member 5% is thus rigidly mounted to the switch shaft M3 and turns when the shaft is rotated. Attached to the insulating member 54 by rivets 53 is the metal plate 55, which has contact finger extensions formed by diagonal bends, as shown at 56 and 5?, and is made of brass or other suitably conductive material having spring qualities. The contact finger extension 56 bears against the stationary contact strip M and the finger 57 bears against the contact strips 45, 48 or as the switch moved to various operating positions. It will be evident that the diagonal bend in the contact finger provides a contact surface which slides somewhat sideways over the stationary contacts as the switch shaft is rotated, providing what is effectively a wider sliding surface thereby reducing the Wear and, yet, still retaining essentially the line contact which is the desirable construction for electrical contact surfaces.

The downward pressure provided by the bracket 32 bearing on the shoulder formed by the reduced diameter upper portion of the shaft 42 provides the necessary pressure which acts through the shaft 42 and the insulating member 54 to cause the contact flexible fingers 56 and 51 to bear firmly against the stationary contact plates 44, 46, 48 and 50. Also mounted in the shaft 42 is the pin 16 which assumes a position between the contact member 5| and 52 when the switch is in the neutral position as shown in Figure 2 and is adapted to contact either the member 5! or 52 when the shaft 42 is rotated to an operating position.

Attached to the base plate AZ by the bolts 94 is the bracket in which is threaded the set screw 9!. The bracket 90 and the set screw 91 retain the case 88 in which is mounted a flasher and relay assembly. The flasher and relay as sembly case 88 is covered by a layer of insulating material which is of a or other suitable insulating material to prevent grounding of the contact members 5! and 52 by contact through the flasher case 88 and flasher mounting bracket 90. The flasher and relay assembly may be of the type disclosed in the patent to Schmiclinger No. 1,979,349 and provided with an auxiliary contact, or a similar flasher of suitable operating characteristics as will be hereinafter described. Extending outwardly from the base of the flasher case 88 are three connection lugs 9 l, 92 and 93. In the interest of clarity, wiring has been omitted from the Figures 1, 2 and 3. The interconnection wiring of the switch assembly contacts and the flashed contact lugs will be evident from the electrical diagram shown in Figure 13.

Also riveted to the base plate I2 is the pilot light lamp socket 96 in which is mounted the pilot light lamp 98. Mounted in the top of the switch case directly above the pilot lamp 153 is the transparent jeweled element 99 which is so positioned as to be in the view of the operator.

Riveted to the top surface of the inmber 64 by means of the rivets 2% is the member 262 having the turned up wing extensions Hi l.

The scissors members 2% and 2H3 are provided with bores 2H and 242 which are mounted on a reduced diameter upper portion of the shaft 42 and rest on the shoulder 2% formed thereby. The right hand ends of the scissors member are provided with the upturned ears and 214% which are adapted to engage the bracket member 32. The left hand ends of the scissors members 2'38 and 21:) mount the tension spring 2 iii. The scissors members 293 and Zlll are also provided with the upturned portions 2|? and .218, respectively, which are provided with the extensions H9 and 226, respectively.

The bimetallic elements 222 and 22d are mounted to the top portion of the bracket as by means of the rivets 225 and 228. The set screws 230 and 232 are provided to adjust the positions of the bimetallic elements as will be hereinafter de scribed.

Mounted on each of the bimetallic elements 222 and 224 are two slotted elements 233 which are made of ceramic or other suitable heat resistant insulating material. The elements 233 provide mountings for the heating. coils; 234 and 2-36: The bimetallic elenfentsare reduced in. width? be tween the ceramic elements 233 show-mat 23A to a width slightly less than the spacing" bet-ween the ceramic elements: Thus the b-iinetallic' el'e ments are permitted to bend freelyina genera-l 1y curved form wl'len they are heated and the relatively stiff brittle ceram-ic elenients are; per mitted to: retain their normal straight form when thebimetallic'elementsbend. I

Anixed to theupper surfaces of the bimetallic strips in the space betweenthe coil mounting elements 233 are strips 237- of asbe's'tos or other suitable heat insulatin'g'mate'rial-l- The heat insulating strips 237 prevent the bimetallid elements from'being heated on their top surfacesby the heating coil to the samedegree as they are heated on their bottom surfaces;- This; differen tial in heating'serves to provide" a greater deflection in the bimetallic element than wouldnor m'allyoccur if the both surfacesof the element were heated uniformly. lChe ceramic coil mounting elements 2-33 serve not" only to insulatethe coil windings from the bimetallicelements but also" permit more free circulation of air through the coil windings thus accomplishing a more rapid cooling of the heating coil and element after the heating coil is dee'nergized. When the switch operating lever 84 is in the position shown in Figures 1-4, the switch is in what will be hereinafter referred to as the neutral position. The switch is heldin this position by the action of the tension spring 236 pulling together the left hand ends of the scissors mem bel's 203' and 2M and by the" action of the upturned portions 7:?! land 2I'8 of the'le-ft hand ends of the scissors members bearing against the sides of the left hand end of the member 64.

Referring to Figure 13 showing the electrical circuit employed in the present invention'the're is shown generally at IN; the wiring diagram of the control switch assembly including within the outline 88 the flasher and relay assembly having connection points 9|, 92 and 93 and which will be hereinafter described in detail. Alsoincluded within the switch assembly is the pilot light 98, the switch contact arm 55 and its associated contacts 44, at, all and 5d, and the grounded pin iii in the switch shaft and its associatedcontact I members EI and the contact members 51- and 5-2 being connected respectively 'to' the heating coils 23 i and 235. Both the arm 55' and the pinit are affixed to the switch shaft 42 as has been previously described.

The battery Hi2 which is generally the battery included in the electrical system of" the motor vehicle on which the signal system is installed, is grounded in the conventional fashion through conductor its to ground H34,- the other side of the battery is connected through lead wire IOfi, fuse member Iiit and lead wire IIEI' to the connection point ti of the flasher and relay assembly.

The signal lamp circuits include the front and rear right hand turn signal light H2 and [14, respectively, the left hand front andrear turn signal lights H6 and H6, respectively, the rear stop light I26, at I22 a conventional stop light control switch which operates from the vehicle braking system. The flasher and relay assembly comprises an arr-nature member iii? around which is wound the armature c'ofl I35? and on which is mounted the movable contact arms I 25 and i28.- The flasher operation is-con trolled by the current limiting resistor 13 6 and the thermal element I38 which are made of a high resistance heat resistant wire: Theater-mar spring action! of the flexible: contact: arm: I525 urges the arm to move toward the armature? and to contact the contact I341.- However;: the? ther mal element lea extending between thearm I and the fixed point I3?v holds the arm" I 26; away" from the contact F341 1 1 'Wh'en? a potential is applied across. the? connection points. at? and 92: a current" will flow through the armature coili I38, resistance: r363 thermal. element I33 and through the arm I25" to: the connection point 9 2. This current flow is limited by the current limiting resistor r36 to a value? which will not-produce sunicient' magnetic held to cause the flexi'ble'contact'arm' I28, which: is held' in open position by its own springaction; to be drawn against the armature I 242 Thecu1"- rent is sufiici'ent, howeverjto'he'at the thermal? element I38 which; upon heating expands, thus allowing the contact arm I25 to= move inwardly gradually and; after" a period ortime, 'preestab'- lished for'thevalue" of potential applied; to' ma'ke'. contact with contact I34; Whenthis contact ismade the current flow will increase to a value: determined by the capacity of the lamp inv the circuit, and the increased current flow through the armature coil t3!) will" produce 'a sufiicient magnetic field to hold the contact arm I 28 firmly against the armature I24 and also mamas will be hereinafter describedg cause' the contact arm L28 to close against the armature "i'M 'an'dcon tact I 32.

When the contact arm I 26 engages contact I'3'4' the high resistance I36 and the" thermal element I38 are bypassed reducing thecurrnt through the thermal element to essentially a zero value, thus permitting the thermal el'ernentto cool and contract. When the tension developed in= the thermal element by contractiontherein is suffcient' to overcome themagn'etic eifort of the armature' n'el'd themovable' arm I26"willbe drawn away from the armature I24- opening the contact I341 The current limiting resistor Iii-'5 and'the thermal element I38 are thus again includedin the circuit and another period of heating'is begun during which time only a limited current will now through the circuit. During this period of limited current flow through "the coil I the contact arm I23 will by its own spring'action bedrawn from the armature IN and the contact I32 will be open.

With the switch operating lever in the position shown in the Figures" l d-"the movable switcn arm will be in the position connecting contact points id and 4'8, asshown in Figure 13;

With the switch in this position an operation or the stop light switch I22, which will occur in a conventional" fashion in conjunction with an operation of the vehicle braking system will establish a circuit permitting current toflowfrom the battery I02, one: side of which is ground-- ed at led, through the lead wire I06, fuse member I08, lead wire Hit), armature coil I30, current limiting resistor I36, thermal element I38, contact arm I26, lead wire MB, signal switch parts 44, 55 and 48, lead wire I42, stop light switch I22, lead wire I44-,'and' stop light lampl20 to thecommon ground I04;

Due to the high resistance of the pathv through the limiting resistor I36; and the thermal ele ment I38, insuflicientcurrent will pass toillumi nate the lamp I2ii The current is sufiic-ien-t, however, to heat the wire I36 The heate d wire expands allowing the contact arm I26 to move inwardly toward the armature I24 and to ultimately make contact with the contact point 34. When this contact is established the resistor I36 and the thermal element I38 are bypassed and low resistance circuit is established through the flasher, and the current flow is dependent upon the resistance of the lamp member I20.

The current which flows through the armature coil I30 when the lamp I20 is illuminated creates a magnetic held in the armature I24 of sufiicient intensity to close contact member l28 against the contact point I32 thereby closing the circuit between connection points 92 and 03 permitting current to flow from the battery 502 to contact point 92 as has been previously described and from connection 02 to connection point 93, through connecting wire I50, the lamp St and through wire I52 to the common ground I04.

The stop lamp I28, the turn signal lamps H2 and H4, and the turn signal lamps H6 and H8 are selected. to be of such capacity that each of the three circuits normally draw the same amount of current when all the lamps are operative. The spring tension of the contact arm I28 of the flasher assembly is selected to be such that a current less than the normal current through any of the signal circuits will not produce a field of sufficient intensity in the armature I24 to pull in the arm I28 and close the contact I32. Thus failure in any of the lamp circuits will cause the pilot light to become inoperative and thereby provide for the operator an immediate indication of any failure in the signal system.

As has been hereinbefore described, upon the closing of the contact arm I26 against contact point I34 substantially no current will flow through the resistance I36 and the thermal ele ment E38. Thus, the thermal element will cool and contract and, when suflicient tension has developed, will draw the contact arm I25 away from the armature I24 breaking the contact at I34 and again imposing into the circuit the resistance I36 and the thermal element i355 thus limiting the flow of current through the circuit to a value below that which is required to illumimate the lamp I20.

This reduced current value through coil I30 is immediately followed by a reduction in magnetic field whereupon the contact arm E38 will drop out, opening contact I32, interrupting the current through the pilot lamp. After a heating interval the thermal element I35 will again have expanded sufliciently to allow the contact arm I26 to move inwardly making connection with contact I34 and the above described operation is repeated. Thus there exists a flasher system which, so long as a circuit is completed to ground, will continue to operate and if the current passing through the coil I30 is above the value required to create suflicient magnetic field to close the contact member I28 against its own spring tension, the member I 28 will close and open in conjunction with the flashing operation of the flasher, thus causing the pilot light to blink simultaneously with the blinking of the signal lamp.

When the operating lever 60 is moved by the operator to a position to indicate, for example, a right hand turn as shown in Figure 5, the movable switch member 55 will assume a position 55' shown. in construction lines in Figure 13 connecting the contact 44 with the contact 583. In this position of the signal switch the current flow from the battery I02 through the fuse I08 and the flasher assembly, as hereinbefore described, connecting wire I40, contact member 44, 55 and 50, the wire I54 and to the right hand front and rear signal lamps H2 and H4, respectively, to the common ground I0 4. It will be evident that the turn lights H2 and H4 will cause the flasher to operate in a manner identical to that as described in connection with the operation of the stop light I20.

When the operating lever is moved to a position to indicate a left-hand turn the switch member will assume the position shown by 55", the left-hand turn lamps H6 and I18 will be energized and the system will operate as described above in connection with the right-hand turn lights.

It should be noted that when the signal switch member 55 is in the position of contacting either contact member in the case of a right hand turn, or contact member in the case of a left hand turn, that a simultaneous operation of the stop light switch 522 will not cause a current to flow through a stop light I293 because of the fact that there i an open circuit between contact members 44 and 48.

Referring to Figure 5 it will be observed that when the operating lever is moved upwardly to a turn position as described above, scissors member 2298 will be rotated about the shaft 42 as a result of the engagement of the turned up portion 25? of the scissors member 2 28 with the side of the left hand end portion of the member 64. When the member 54 and the scissors member have been thus positioned the right hand of the thermal element 224 as a result of its own spring force will move downwardly as the extension 21s of the upturned portion iii of the member moves out from underneath the thermal strip. When the parts have assumed these positions, it will be observed that the spring 2H5 has, been expanded and is acting to pull the left hand end of the scissors members together, and by virtue of the engagement of the upturned portion 2 l l of the scissors member 23%! with the mem ber 54 the spring 2IE also serves to provide a force urging the member to return to a neutral position. The return of the scissors member 2518 to the neutral position is prevented by the thermal element 224 the edge of which is in engagement with the side of the extension 2I3 of the upturned portion 2H of the scissors member 268. Return of the member .4 to the neutral position is resisted by the engagement of the end of the thermal element 224 with the inclined edge of the upturned portion 204 of the member 2:32.

It will be noted that the adjusting screws 230 and 232 shown in Figure 3 provide means for adjusting the positions of the right hand ends of the thermal elements to provide for proper engagement of the members 2 I H and 2.22 by the thermal elements.

Manual return of the switch assembly to the neutral position may be accomplished by the operator drawing the operating lever downwardly to the neutral position causing the inclined edge of the winged extension 2&4 of the member 252 to ca m the thermal member upwardly and to pass under the thermal element to the neutral position. After the thermal element has been lifted suihciently by the portion 2134, the extension 253 of the upturned portion 2 ll of the scissors member 208 is permitted to pass below the thermal element in response to the urging of the spring 2Iii and again contact the side of the left hand end of the member 64 urging it to assume the neutral position shown in Figure l.

Automatic return of the switch assembly to the neutral position from an operating position after the expiration of a predetermined period or" time is accomplished by the operation of one of the thermal el'er'r'ientsl When the operating lever has been moved upwardly as "shown in Fi g' ure the pin it'which is'grounded'to the switch shaft 42' engagesthe contact member closing the circuit from the battery 1 i2, through the conductor till, ruse H I09, conductor 2 35' and the heating coil 235 to ground through the pin '16 and the switch shaft 42. I

When the heati'rijg co'il 236 is energized the heat generated in the coil willheat the bimetallic ele m'ent"22" l"and as a r 'esult, the right handjend of the bimetallic element will bewde'flected upwardly.

When the deflection of the bimetallic element is sufi icient to lift the end of the element above: the extension ilil'ofthe turned p portion 2i? of the scissors member 265, the scissors member Eillis' free to respond to the urging ofthe spring 2i6" and return to the neutral position carrying with it the member 64. The parts will then assumethe position shownin Figures 154. a v

The switch'lil may be v'ariously positioned. for

convenient operation; for example, on the floor of" the car where it'may be foot-operated and serves to "permit the driver to open the heating coil circuit 'when he desires toextend the" time interval.

during which tlie turn signal lamps will remain energized. The switch I539 is a normally closed switch and, therefore, when not held in openposition by the driverthe turn signal switch will lie-controlled by the normaloperation of theh'eat ing elements and thus the turn signal system cannot be 'rendered'inoperative by forgetfulness on the partof theolriver;

It will be observed that; if immediatelyffol-i bly from the operating position, as shown ini Figure 5, thesw'itch'is 'inanually turned to the" opposite" operating-posi i n; the bimetallic strip] "222 will engage the extension 226 of the turned. up portion ildofthe scissors member Zli] and serve to retain the' switcha'ssembly in the other lowing the automatic release of the switch assemf operating position. When the swit ch has been placed in this position the heating coil 23%! is energized as a re's'ult'oi" the completion of the circuit therethroughbyithe grounding of the contact memb'erEi' bythe pin 16. When the bimetallic'ele'ment 222 "is heated suiiiciently bythe ts, conductor on, switch coil 234 'to ha've'defle'cted'its right hand end pore tion upwardly above the extension 223. of. the,

turned up portion 2] Bof the scissors member 2 ID,

the portion" 258 "oi the scissors member Ziil will returnthe member st to the neutral position as a result of the urgihg'of spring 21s. observed that immediately following an. automatic return of the'switchfrom one operating position the switch may be placed in the other operating po'sitionand an automatic return therefrom be "effected.

It will be In Figures 6; '7 ends there is shown an alternate 1 form of the invention'employing a bracket 24'0i identical with the bracket 32 'shown in Figures l-5,'an d a member iizjand an operating o 244? which are substantially identical to the member 64 and the'operating rod 68 shown in Figures 1-5; Mountedonthe left-hand end the mem ber'zsz' is the ball projection 260. The spring e1e-'. ment 248is mounds-sm bracket Mil by means of screw 246 which is passed through IalOO'p'jin the e'nd of'the spring" wire. The other end or the tion which passes through the bore 250 in the member 242. The curved portion of the spring 248 is of such a form that the spring is at. rest whenthe switch isin the neutral position shown in Figure 6, ,The bores 252 and 254 are provided for alternate reception of, the turned up end portion of the spring to accommodate for reasonable manufacturing tolerances in the i'ormation of the spring. Thus, by inserting the upturned end of the sprin in one of the three holes 258, 252 or 254 theswitch assembly will be in substantially the neutral position shown in Figure 6 when the spring is in a relaxed position. It will be apparent thatmoving the switch to the operating position shown in Figure 7 or to the opposite operating position will deflect the spring and while the switch is held in that position the spring will act to urge the switch assembly t a neutral position.

In this form of the invention the bimetallic elements 262 and 254 are mounted substantially identically as are the elements 222 and 22 i shown in Figures 1-5 and have mounted thereon the heating coils 266 and 288 which are substantially identical tothe heating coils 23d and 236 previously shown In the form of the invention shownin Figures 6, 7 and 8, however, the right handend portions of the bimetallic elements 262 and 26 are inclined upwardly towards each other as is clearly shown in Figure 8 and are also provided with the apertures 216 and 2H, respectivey:

When the switch, constructed in accordance with this form of the invention, is moved to an operating position, for example, as shown in Figure 7, the ball member 2% passes beneath the bimetallic element 264 forcing the element upwardly u ntil the ball enters the aperture fill in the element, Th normal spring tensio in the bimetallic element tends to hold the element down ina position with the aperture surrounding the ball thusretaining the ball within the aperture and retaining the member 242 in the operating position. 7 v I Thus when theoperating rod 244 is moved upwardlyas shownin Figure 7 there is existing the tension of the spring 248 tending to pull the member..2, l2 back to a normal position and the restraining action of the bimetallic element enlyand the ball will pass out of th aperture as the member 242 is moved to neutral position. The spring 2% will hold th member 232 in the neutral position a shown in Figure 6.

When the switch assembly has been manually placed in the operating position as shown in Figcoil 2553 will .be energized by.

ure'lthe heating the completion cithe electrical circuit there through in a similar manner andby similar means a as hereinbefore described in connection with the energizing of the heating coil 2%. The

bimetallic element,is'jarranged so that whenthe heating coil 2til has. been energizedand the bimetallic elementfisfheated thereby theelement will deflect upwardly. as 2 its temperature is in creased. When the element 264 has defiectedupwardl'y't'o a sufficient extent to permit the ball member 26b to be drawn out of the aperture all by the force of the spring 2M; acting on th member 242, the switch assembly will be returned to th neutral position.

It will be apparent that in this form of the invention, as in the previous form, the switch assembly may be moved to either of the operating positions and manually removed therefrom, or the switch assembly may be moved to either of the operating positions and after a predetermined period of time, as determined by the rate of heating of the bimetallic element provided by the heating coil, will be automatically released therefrom. In this form of the invention, as shown in Figure 8, there are provided adjusting screws 212 and 2% identical to the screws 23d and 232 hereinbefore described and by which the positions of the right hand ends of the thermal elements 26d and 262, respectively, may be positioned to provide for proper engagement of the ball member 25563 by the edges of the apertures 210 and 21 I,

In the form of the invention shown in Figures 9, and 11 there is provided the bracket member 280 which is similar to the bracket member 32 previously described herein except that in this form of the invention the top portion of the bracket 28% is provided with a flat extended portion 296 within which is formed depressions 291, 298 and 299. The bracket 2863 mounts the switch shaft 282, the member 284 mounting the operating lever 28 I.

The spring member 2%- is mounted to the bracket 280 by means of the screw 2% which is passed through a loop in the end of the spring. The other end of the spring 236 is provided with a turned up portion which is passed through the bore 235 in the member 2%. There is provided the alternate bores 23'! and 289 to accommodate normal manufacturing tolerances of the spring to permit the parts to be assembled with the switch assembly in a substantially neutral position when the spring member is at rest. The structure and operation of the spring in this form of the invention is substantially identical to that described in connection with the form of the invention shown in Figures 6 and 7.

In the form of the invention shown in Figures 9, 10- and 11 the bimetallic elements 292 and 294, which are shown in construction lines in Figures 9 and 10 to permit greater clarity of the showing of the other portions of the figures, are similar to those hereinbefore described in connection with the previous forms of the invention and mount heating coils which are identical to those hereinbefore described in connection with the previous forms of the invention. The right hand ends of the elements are bent downwardly as shown at 295 and the elements are adapted to bend downwardly when their associated heating coils are energized and the elements are heated thereby.

The left hand end of the member 284 contains an aperture within which is mounted the ball 300 and attached to the turned down portion 302 of the left hand end of the member 28 2 are the leaf spring members 304 and 388. As clearly shown in Figure 11, the spring member 306 engages the top of the ball 300 serving to press the ball downwardly against the plate 296 and to hold it in position in one of the depressions 297, 298 and 299 into which it may fall as a result of operation of the switch assembly.

Pivotally mounted to the turned up portions 308 of the member 284 by means of the pin 309 is the release member 3H) being formed at its right hand end portion, as viewed in Figure 11, with a downward bend terminating with the upturned end portion 3 E2. The left hand end of the member 3m passes through an opening in the upturned right hand end of the member 306.

In this form of the invention when the switch assembly is moved to an operative position, for example, as shown in Figure 10, the urging of spring 2% tends to return the member 284 to the neutral position. However, when the switch assembly is in this position the ball 300 is: seated in the depression 29? and held therein by the member 3116 with sufrlcient force to prevent the return of the member 284 to the neutral position. When the switch is in this position the heating coil (not shown) on the bimetallic element 292 is energized as a result of the contact established between the pin 3M and its associated contact member 356 which serves to establish a circuit through the heating coil in the same manner as the circuit was established through the heating coil 23% in the form of the invention first described. It will be observed by viewing Figure 10 that when the switch is in this position the right hand end of the bimetallic strip 292 terminates above the turned up portion 312 of the member M0. With the parts thus positioned when the bimetallic strip 292 is deflected downwardly as a result of being heated by its. associated heating coil that the right hand end of the bimetallic strip will press downwardly the right hand end of the member 3"] and lifting the member from engagement with the ball and thus permitting the ball to rise out of the socket till and permitting the member 255 5 to be drawn to the neutral position as a result of the urging of the spring 286.

In Figure 11 there is shown in construction lines the right end of the thermal element 2&2 in the position it would assume when heated and deflected downwardly. It will be observed that the downward bend in the member 310 provides clearance permitting the switch to be locked in the neutral position by the action of the member 3M5 pressing the ball 300 into the depression 298 and also provides sufiicient clearance in order to permit the switch to be turned into the other operating position bringing the end of bimetallic strip see over the upturned end 3l2 of the member Silt without there being engagelent between the depressed end of the bimetallic strip 232 and any portion of the member 310.

Referring to Figure 12 there is shown still another modification of the present invention in which the bracket 3% mounts the switch shaft 32! which mounts the member 322 and the scissors members 325 and 326. The spring 328 is. connected to the right hand ends of the two scissors members and is adapted to draw the ends together. These scissors members are identical to those described in connection with the form of the invention shown in Figures 6, 7 and 8.

In this form of the invention the member 324 carries the extended portions 339 and 332 are similar to the extended portions 86 shown in the form of the invention hereinbefore described. In this form of the invention, however, the end of the member 230 is provided with the hook portion 33! and the end of the extension 332 is provided with the hook portion 333. There are also provided the sliding latch members 334 and 335 which contain the slots 336 and 331, respectively, and are thereby slidably mounted on the pins 338 and 339. The latch members 334 and 335 are held in position by the action.

amazes 13 of the tension springs 340 and 34! both of which are fixed to brackets mounted to the member 342. Member 342 serves to retain the flasher element 344 which is identical to element 88 as hereinbefore described. The member 342 also mounts the bimetallic strips 344 and 345.

lhe bimetallic elements 344 and 345 mount the heating coils 346 and 341, respectively, in a manner substantially identical to the mounting of the heating coils hereinbefore described in the other form of the invention. The right hand ends of the bimetallic elements 344 and 345 as viewed in Figure 12 are provided with the outwardly turned portions 348 and 349, respectively, which are adapted to engage the latch members 334 and 335, respectively, as will be hereinafter described. There are also provided the stop pins 350 and 35E which engage the inclined end surfaces 352} and 353, respectively, of the latch members 334 and 335.

When the switch constructed in accordance with this form of the invention is moved to the operating position as shown in Figure 12 the hooked end portion of the member 333 rides over the inclined end surface 352 of the latch member depressing the end of the latch inwardly pivoting the latch member about the mounting pin 336. When the hooked end 33! has passed beyond the end surface 252 the latch member 334 acting in response to the tension applied by spring 3% will resume its normal position which is shown in Figure 12. In this position the hooked portion 33! of the member ass is in engagement with the catch formed by the end of the inclined surface 352 of the latch member It will be apparent that by providing a spring 346- of sufiicient tension the member 322- is prevented from being returned to the neutral position, as a result of the urging ofthe spring 328 acting on the member 322 through the scissors member 324 on the member 322.

In this form of the invention when the switch is manually returned to the neutral position the hooked end 553i which is in engagement with the end ofv the latch member 334-will pull the latch member 334 to the right extending the spring 34c and causing the inclined surface 352 to be cammed inwardly as it slides past the stop pin 35%. When the latch member .334 is pulled to the right a sumcient distance and caused to rotate about the mounting post 338 as a result of the camming of the surface 352 against the stop pin 359, it will be apparent that the hooked end portion of the latch member 334 will be drawn clear of the hooked end portion 33I of the member 33 1! permitting'the member 322 to be returned to the neutral position andpermitting the latch member 334 to'be returned to its normal position by the actionoi the spring 340.

When'the switch assembly has been placed in the operating position as shown in Figure 11 the pin 354cm the switch shaft will engage the contact member 356 and will close thecircuit through the heating coil'346 in the samefashion that the heating coil circuit-was completedin the. form of the invention first described. In this form of the invention thebimetallic element 344 is adapted to deflect outwardly as it is heated by the heatingcoil 346 and bear'against the latch member 334 causing the latch member 334 to rotate about the mounting pin 338. When the bimetallic element 344 has deflected outwardly. toa sufficient degree to cause the hooked end of thelatch member 334 to release the hooked I comprising rotatable. switching meansfhaving a plurality of contact positions, means for urging; the switching means from one of its; contact posiend 33i of the member 330 the member 322 and the switch assembly will be returned to the neutral position as a result of the tension spring 333 acting through the scissors member 324 on the member 322.

It will be observed that in this form of the invention there is provided a latch member 335 and its associated parts adapted to latch the, switch assembly in its other operating position and a bimetallic element 335 and its associated parts adapted to automatically release it therefrom independently of the condition of deflection of the bimetallic element 344.

t will be apparent that the present invention provides, as set forth in the various embodiments, an automotive signal system switchingmechanism having an automatic return from its: normally operative positions to its neutral position. The automatic return is completely independent of the operation of the motor vehicle,, for example, the turnin of the steering wheel is sometimes used to effect the return and it is independent of the operator.

It will also be noted that in all forms of the invention disclosed herein the thermally actuated release mechanisms associated with each of the signal switch operating positionsare independent of each other in. their operation. This is of considerable importance in view of-thefact that an operator after having placedthe, switch in one operating positionmay desire immediately thereafter to place the switch in the other oper ating position. It will be apparentthat in. all forms of the invention, as hereinbeforeset forth,v this is permissible even though the thermal element associated with the position infwhich the. switch was first placed may have been heated, to a substantial degree and was about to-or had,

actually released. the latchingv mechanism hold ing the switch assembly in thatposition,

The invention as disclosed. herein contains.

various other novel features such asthe mounting of the heating coils on the bimetallic elements and the application of the heat insulating strip of the material on one side of. the bimetallic element. The employment of the heat insulating strip in this structure provides for a maximum degree of deflection of the bimetallic element.

the maximum possible rate of cooling of boththef coil. and the bimetallic element. Thus thebi-- metallic element will cool to a normal,temperalture, at which it will assume its normal at rest position, in a minimum period'of time.

It will be apparent that the switch return spring arrangement shown in Figures 6-11 and, the spring and scissors switch return mechanism,

shown in Figure 12 may be used interchangeably. It will also be apparent thatv various other modifications may be made in the form of the inven-j tion disclosed herein without departing from the. scope of the invention as set forth in the following. claims.

What is claimed is:

1. A time delay release control switch assembly tions to another of its contact positions, means engaging and retaining said rotatable switching.

means in said one of its contact.positionswlienit is rotated thereto, and thermally responsive means for releasing the engaging and retaining means to permit the urging means to rotate the switching means to said other of its contact positions.

2. A time delay release control switch assembly comprising a manually operated rotatable switching means having a plurality of contact positions, means for urging the switching means from one of its contact positions to another of its contact positions, means engaging and retaining said rotatable switching means in said one of its contact positions when it is rotated thereto, and thermally responsive means for releasing the engaging and retaining means to permit the urging means to rotate the switching means to said other of its contact positions after said switching means has been retained in said one of its contact positions for a predetermined pe iod of time, said engaging and retaining means being releasable by manual rotation of said switching means to said other of its contact positions before the expiration of said predetemined period of time.

3. A time delay release control switch assembly comprising rotatable switching means having a plurality of contact positions, means for urging the switching means from one of its contact positions to another of its contact positions, means engaging and retaining said rotatable switching means in said one of its contact positions when it is rotated thereto, thermally responsive means for releasing the engaging and retaining means to permit the urging means to rotate the switching means to said other of its contact positions after said switching means has been retained in said one of its contact positions for a predetermined period of time, and means for extending said predetermined period of time.

l. A time delay release control switch assembly comprising rotatable switching means having a neutral position and an operative position on each side of said neutral position, means for ur ing the return of said switching means from each of its operative positions to its neutral position, independent means engaging and retaining said rotatable switching means in either of its operative positions when it is rotated thereto, and independent thermally responsive means for releasing the engaging and retaining means to permit the urging means to rotate said switching means from either of its operative positions to its neutral position.

5. A time delay release control switch assembly comprising rotatable switching means having a plurality of contact positions, means for urging the switching means from one of its contact positions to another of its contact positions, means engaging and retaining said rotatable switching means in said one of its contact positions when it is rotated thereto, means including a thermally responsive element for releasing the engaging and retaining means to permit the urging means to rotate the switching means to said other of its contact positions, coil mounting means mounted on said thermally responsive element, and a heating coil mounted on said coil mounting means in spaced relation with said element, said mounting means and said element being constructed and arranged to permit the element to bend substantially arcuately when heated by the heating coil while the coil mounting means retains its normal form.

6. A time delay release control switch comprising rotatable switching =ans having a plurality of contact positions, for urging the switching means from one of its contact positions to another of its contact positions, means engaging and retaining said rotatable switching means in said one of its contact position when it is rotated thereto, means including a flat thermally responsive element for releasing the engaging and retaining means to permit the urging means to rotate the switching means to said other of its contact positions, coil mounting means mounted on said thermally responsive element, a heating coil mounted on said coil mounting means in spaced relation with both sides of said flat element, and means providing a greater degree of heating of one side of said flat element by said heating coil than of the opposite side of said flat element by said heating coil.

'7. A time delay release control switch assembly comprising rotatable switching means having a plurality of contact positions, means supporting said switching means, means for urging the switching means from one of its contact positions to another of its contact positions, means engaging and retaining said rotatable switching means in said one of its contact positions when it is rotated thereto, and thermally responsive means for releasing the engaging and retaining means to permit the urging means to rotate the switching means to said other of its contact positions, said urging means comprising not more than one convolution of a single arcuately formed spring element joining said switching means and said supporting means.

8. A time delay release control switch assembly comprising rotatable switching means having a plurality of contact positions, means supporting said switching means, means for urging the switching means from one of its contact positions to another of its contact positions, means engaging and retaining said rotatable switching means in said one of its contact positions when it is rotated thereto, and thermally responsive means for releasing the engaging and retaining means to permit the urging means to rotate the switching means to said other of its contact positions, said urging means comprising a single arcuately formed spring element joined at its ends to said switching means and said supporting means, and means providing for the joining of one end of said spring element in alternate position to provide adjustment of the urging applied to said switching means by the spring element.

9. A time delay release control switch assembly comprising rotatable switching means having a plurality of contact positions, supporting means pivotally mounting said switching means, means for urging the switching means from one of its contact positions to another of its contact positions, means engaging and retaining said rotat able switching means in said one of its contact positions when it is rotated thereto, and thermally responsive means for releasing the engaging and retaining means to permit the urging means to rotate the switching means to said other of its contact positions, said urging means comprising a pair of scissors members pivotally mounted on said supporting means and means urging said scissors members together, said scissors members being separated by rotation of said switching means from said other of its contact positions to said one of its contact positions.

10. A time delay release control switch assembly comprising rotatable switching means having a plurality of contact positions, means for urging the switching means from one of its contact positions to another of its contact positions,

and means including pivotally mounted scissors members and a thermally actuated element for retaining said rotatable switching means in said one of its contact positions when it is rotated thereto, the thermally actuated element being operable to release the scissors members to permit the urging means to rotate the switching means to said other of its contact positions.

11. A time delay release control switch assembly comprising a manually operated rotatable switching means having a plurality of contact positions, means for urging the switching means from one of its contact positions to another of its contact positions, and means including a thermally actuated element for retaining said rotatable switching means in said one of its contact positions when it is rotated thereto and thereafter releasing the retaining means to permit the urging means to rotate the switching means to said other of its contact positions.

12. A time delay release control switch assembly comprising rotatable switching means having a plurality of contact positions, means for urging the switching means from one of its contact positions to another of its contact positions, means including a protrusion and a cooperating socket retaining said rotatable switching means in said one of its contact positions when it is rotated thereto, and thermally responsive means for releasing the protrusion from the cooperating socket to permit the urging means to rotate the switching means to said other of its contact positions.

13. A time delay release control switch assembly comprising rotatable switching means having a plurality of contact positions, means for urging the switching means from one of its contact positions to another of its contact positions, means including a member, a cooperating socket and means urging the member into the socket for retaining said rotatable switching means in said one of its contact positions when it is rotated thereto, and thermally operated means for relieving the member from the urging of the member urging means for releasing the retaining means to permit the switch urging means to rotate the switching means to said other of its contact positions. a

14. A time delay release control switch assembly comprising a manually operated rotatable switching means having a plurality of contact positions, means for urging the switching means from one of its contact positions to another of its contact positions, means including a pivotally mounted latch retaining said rotatable switching means in said one of its contact positions when it is rotated thereto, and thermally operated means for releasing the retaining means to permit the urging means to rotate the switching means to said other of its contact positions.

ALFRED HOPKIN, JR.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,043,470 Dyer et a1. June 9, 1936 2,264,027 Holmes Nov. 25, 1941 

